Database Administration Questions

SELECT "column_name"

FROM "table_name"

WHERE "column_name" IS NULL.

Telnet uses TCP at layer 4. It uses IP at layer 3. We know that Telnet uses TCP/IP protocol, but in the question, it is asked specifically at layer 4 what is used in Telnet. So it is TCP at layer4 and IP at layer 3.

A Sandal.

It has sticking strips to make them fit for our feet. If you bind them only you can start walking or other wise it comes out.

Let the required number be 'X'

Condition 1 :  

$$\begin{gathered} XX = 2X \\ => 2X2 = X \\ => X = 12 \end{gathered}$$

Condition 2 :

$$\begin{gathered} X × X = X2 \\ => X = 12 \end{gathered}$$

Therefore, 12 is the number which becomes double when it is divided by itself and becomes half when it is multiplied by itself.

A Temper.

Entity is a real world object

Component Testing is also called as Module or Unit or Program testing. It is testing of all the components in an application separately.

Compact disc (CD) is a digital optical disc data storage format that was co-developed by Philips and Sony and released in 1982. 

These are actually made to replace floppy disks that were used to store files and programs from the computer.

The format was originally developed to store and play only sound recordings but was later adapted for storage of data (CD-ROM).ese CD's uses Laser technology.